Electric heater



Jan. 15, 1963 L. c. HANSON 3,073,942

ELECTRIC HEATER Original Filed May 4; 1959 2 Sheets-Sheet 1 INVENT OR. 7

Jan. 15, 1963 c. HANSON 3,073,942

ELECTRIC HEATER Original Filed May 4, 1959 2 Shefs-$heet 2 I INVENTOR. 11c 37 37 [erg fffazzgs'azz United States Patent "ice 3,073,942 ELECTRIC HEATER Leroy C. Hanson, Eimhurst, Ilh, assignor to Ferro Corporation, (Ileveland, Ohio, a corporation of Ohio Continuation of application Ser. N 810,835, May 4, 1959. This application July 1%, 1960, Ser. No. 43,9d1 14 Claims. (Cl. 219-37) This invention relates to electric heaters of tubular sheath resistance type wherein a plurality of sheath end portions are collectively combined in a localized grouping thereof, and has reference more particularly to an assembly of such end portions and the pivotal mounting thereof, this application being a continuation of my application Serial No. 810,835 filed May 4, 1959, now abandoned.

The invention is particularly advantageous for surface heating units such as are commonly employed for cooking purposes in ranges and the like, as such heating units are usually constructed of tubular sheathed resistance elements shaped in the form of a fiat spiral winding which constitutes the active heating portion of the heater and is mounted in an opening in the range top to support a cooking receptacle or vessel thereon, and the end portions of the said elements are extended laterally from the range top opening at one side thereof, oftentimes in a manner in which the present invention is applicable thereto, to a place underneath the range top where the terminal wires, which project from said end portion for attachment of current supply conductors thereto, are not exposed to spillage from cooking operations on the winding.

Such surface heaters are usually pivotally mounted at one side of the range top opening so that the winding or active portion may be swung away from the range top opening to one side thereof for cleaning access to a combined spillage collection and heat reflector pan which is usually provided underneath the winding, and the terminal end portions of the sheathed elements of the winding are usually extended outwardly underneath the range top approximately at the place of pivotal mounting in a grouped relationship, such as contemplated herein, which will facilitate pivotal movement and permit convenient connection of current supply conductors to the terminal wires projecting from the ends of the terminal end portions of the sheaths.

Spillage oftentimes occurs in using such surface heaters and, as such spillage may reach the terminal ends of the sheaths through the assembled end portions thereof and detrimentally affect the operation of the heater, it is desirable that the assembly be safeguarded against passage of such spillage therethrough.

The principal objects of the invention are to provide an improved assembly of end portions of the sheaths of heating elements of tubular sheathed resistance type; to

insure positive locking of the sheath end portions in the assembled relation to one another; to preclude communication of spillage through the assembly; and to simplify and improve the pivotal mounting of the heater, these and other objects being accomplished as pointed out more particularly hereinafter and as shown in the accompanying drawings, in which:

FIG. 1 is a top View of a portion of a surface type heating unit showing the place of pivotal mounting of the heater in accordance with the invention;

FIG. 2 is a side view of the FIG. 1 portion of the heating unit as viewed from the bottom of FIG. 1 and showing the pivotal mounting of the heater;

FIG. 3 is a bottom View of the portion of the heating unit shown in FIG. 2;

FIG. 4 is an enlarged sectional view on the lines 44 3 ,373,942 Patented Jan. 15, 1963 of EEG. 2 taken through the pivotal mounting of the heater;

FIG. 5 is an enlarged side view of the end portions of the tubular sheath of the heater as assembled for application in the pivotal mounting;

FIG. 6 is a side view of the sealing element which is interposed between the sheath end portions of FIG. 4;

FIG. 7 is a fragmentary side View of a sheath end portion showing a modification thereof for sealing purposes; and

FIG. 8 is a sectional view of assembled sheath end portions sealed in accordance with the modification of FIG. 7.

Referring to the drawing, which shows a preferred embodiment of the invention, the heating unit and pivotal mounting or hinging of the heater is generally similar to that of Anderson and Hanson Patent No. 2,834,863, the resistances, however, being individually enclosed in insulating material in separate tubular sheaths which are shaped in flat spiral form with coils or convolutions thereof intercalated, as in Kelly Patent No. 2,831,100, to provide a flat winding in the form of a fiat grid which constitutes the active heating portion of the heater and has end portions of the sheaths extending downwardly and laterally from the winding and grouped together in a sleeve by which the heater is pivotally mounted or hinged for tilting upwardly in the manner proposed in Tuttle Patent No. 2,508,552.

A portion only of the flat winding is shown in the drawing and indicated as a whole by the reference numeral 1i) and is composed of two tubular sheathed resistor elements 11 and 12 of conventional construction which are spirally shaped in customary manner to provide respective coils 3.1 and 12 which are intercalated to provide the fiat winding 19.

This winding 10 is shown mounted in the customary manner till the open top of a mounting ring 13 for reception in an opening 14 of a range top panel 15 and the mounting ring has an annular flange 16 which extends outwardly over and rests upon the range top panel and has a generally tubular depending annular wall or skirt portion 17 which extends downwardly through the range top opening and is provided around the bottom with an inturned portion 18 providing a supporting ledge on which a conventional combination drip pan 19 and reflector is supported, the latter having an outwardly projecting rim 20 around the top which rests on the ledge 18.

The winding 10 removably rests on and is supported in horizontal position in the open top of the mounting ring by a spider 21 having radially disposed arms which underlie the coils or convolutions of the winding'and the skirt portion 17 of the mounting ring is provided at suitable intervals therearound with outwardly pressed portions providing seats 22 on which the outer ends of the spider arms rest for supporting the spider.

The winding is thus liftable off of the spider and both the spider 21 and the pan 19 are removable from the mounting ring 13.

Each heating element 11 and 12 has its opposite end portions arranged to extend conjointly in the same generally tangential direction from the periphery of the winding, but at a downward inclination therefrom, through an opening 23 in the skirt portion 17 to a place at the exterior thereof where said end portions are conjointly journaled in a bearing, which is indicated generally at '24, to provide a pivotal connection of the heater with the mounting ring permitting the winding of the heater to be swung upwardly from its horizontal position on the spider 21 to an upraised position at that side of the ring where the heater element ends extend through the skirt opening 23.

The opening 23 in the skirt is an open bottom notch permitting convenient assembly of the heater and mounting and this notch is normally closed at the bottom by the rim 20 of the pan 19.

The opposite end portions of the heating elements which are thus extended tangentially downward and conjointly jonrnaled in the bearing are individually identified for convenience, the end portions of the element 11 being indicated at 11 and 11 and the end portions of the element 12 at 12' and 12.

Each of the heating elements 11 and 12 comprises a tubular sheath 25 having a heating resistance 26 extending lengthwise therein and embedded in compacted electrieal insulation 27 in a manner well known in the art, and as customary in such heating elements, the resistances terminate at a distance from the opposite ends of their sheaths and have terminal wires of low electrical resistance electrically and mechanically connected respectively to the opposite ends of the resistances within the sheath and extending outwardly through and electrically insulated from the end portions of the sheath and projecting beyond the respective sheath end for connection of current supply conductors thereto, and each sheath end portion 11*, 11, 12 and 12 is shown herein with such respective terminal wire 28 embedded in compacted electrical insulation 29 which is usually an extension of the insulation in which the resistance 26 is embedded.

The heating element end portions 11 11, 12' and 12 are arranged to lie in grouped-together adjoining parallel quatrefoil relation, as shown particularly in FIG. 4 to constitute a composite stem for pivotally mounting the heater, and are secured together in this relation by a sleeve 30 which is compressed thereon to clamp the sheath end portions securely together, and for this purpose the sleeve is punched into the valley between each adjoining pair of sheath end portions, as indicated at 31, to provide indentations which lock the said end portions securely in place in the sleeve in parallel relation to one another.

The sleeve 30 is generally cylindrical and formed with an annular reinforcing flange 32 around one end, and this sleeve is preferably punched in as aforesaid throughout only a short intermediate portion of its length as indicated in FIG. 5, leaving opposite end portions of the sleeve in the cylindrical shape, and this sleeve as thus indented not only serves to provide journal engagement in the bearing 24 but the indentations 31 and flange 32 thereof provide simple and convenient facilities for regulating the movement of the sleeve and sheath end portions in the bearing as hereinafter explained.

The heater is provided with a terminal block 33 of electrical insulating material into which the outer extremities of the sheath end portions project and this block is provided with customary cavities to accommodate and enclose the projecting ends of the terminal wires 28 and also connecting facilities by which current supply conductors are securable to the projecting ends of the terminal wires, and as spillagefrom cooking operations may flow or migrate down the sheath end portions to the sheath ends and terminal wires and connections and detrimentally aifect the operation of the heater, barrier means is provided to close the sheath end portions assembly against passage of spillage therethrough.

For this purpose a filler 34 of substantial thickness and of a general cross shape with four arms 35 providing four generally semi-circular seats 36 corresponding to the side wall contour of the sheath end portions, is located in the space defined by the four sheath end portions at the place where the enclosing sleeve 30 is to be punched in at 31 so that when the sleeve is punched in at 31 and the sheath ends clamped together in the assembled relation, the sheath ends are clamped in the seats 36, and the filler 34 has the arms 35 thereof projecting outwardly between the sheath end portions sufficiently so that these arms are compressed between the sheath end portions and the indentations 31 abut against the outer ends of the arms of the cross.

This filler 34 is preferably of a compressible material, such, for example, as a silicone rubber, and when clamped in place as aforesaid provides an effective seal to prevent passage of spillage through the sleeve and sheath end assembly. The annular flange 32 at the outer end of the sleeve 39 serves as a deflector to intercept any drainage at the exterior of the sleeve.

The sheath end portions may be provided, if desired, each with a pair of quarter turn indentations as indicated at 37 in FIGS. 7 and 8 at the place where the filler 34 is to be applied thereto so that each adjoining pair of sheath end portions has an indentation 37 facing a corresponding indentation of the other and conjointly providing a gap between each adjoining pair of sheath ends to accommodate the arms 35 of the filler and thus insure continuity of filler stock between the sheath end portions at that place as indicated at 33 in FIG. 8, and, moreover, the filler, instead of being preformed as indicated in FIG. 6, may be a mass of plastic material which is applied between the sheath end portions before or after they are assembled and forced compactly into place to provide a seal, the employment of a preformed filler as in FIG. 6 being preferred, however, because of convenience of application and assured sealing compression thereof in clamping the sleeve on the sheath end portions.

The bearing 24 which is disposed with the axis thereof in appropriate tangential relation and downward inclination relatively to the winding 10 to hold the winding in proper position of support on the spider 21, is provided by an appropriately shaped bracket, indicated generally at 39, which is secured to the skirt portion 17 of the mounting ring 13, and a companion part, indicated generally at 4%, which is attached to the bracket and both of which are of sheet metal. The bracket 39 is formed to provide a half bearing composed of a top wall portion 41 with an outer side wall portion 42 depending therefrom, and the companion part 40 is of mating half hearing form with bottom wall 43 with upwardly extending inner side wall 44 and this companion part 40, when combined with the half bearing portion of the bracket 39', conjointly therewith forms a bearing in which the sleeve 30 with sheath end portions therein is rotatably confined.

The bracket 39 has a portion 45 extending inwardly from the bearing top wall portion 41 to the skirt portion 17 at which said inwardly extending portion 41 is turned up to provide a wing 46 which is shaped in conformity to the exterior of the skirt portion 17 and secured thereto at one side of the skirt opening 23, as by welding for support of the bracket on the skirtportion 17.

The bracket 39 also has a portion 47 extending forwardly from the bearing outer side wall portion 42 to the opposite side of the skirt opening 23 and has the end portion 48 thereof shaped in conformity to the exterior of the skirt portion and secured thereto as by welding for additional support of the bracket 39 on the skirt portion.

For securing the said mating half bearing to the bracket, the outer side wall portion 42 of the bracket has an offset depending continuation 49 at the bottom with two laterally spaced slots 50, and the bottom wall 43 of mating half bearing 40 has two tongues 51 which project through said slots 50 and are turned down as indicated in FIGS. 2 and 4 for fastening and the half bearing 40 to the bracket, and the upwardly extending inner wall 44 of said half bearing 40 has a lateral extension 52 at the top which is secured by a screw 53 to the bracket portion 45 to cooperate with said tongues 51 to secure the half bearing 40 to the bracket.

The sleeve 30 extends forwardly in the bearing 24 as indicated at the broken away place in the bearing outer side wall in FIG. 2, and beyond the front tongue 5-1 the bottom wall 43 is continued and shaped as indicated at 54 to substantially match the contour of the skirt portion 19 at that place, and at the rear end said wall 43 is provided with a tongue 55 bent as shown in FIG. 2 to embrace the flange 32 of the sleeve 30 to limit endwise movement of the sleeve and sheath end assembly in the bearing and the said flange 32 is provided with an outwardly projecting lug 56 which is positioned approximately a quarter turn distance from the tongue 55 when the heater is in the horizontal position on the spider 21 and which, when the heater is tilted to the desired upraised position for cleaning, is brought into engagement with the tongue 55 and serves as a stop to limit the extent to which the heater may be tilted upwardly.

A ground strap 57 is secured to the underside of the bottom wall 43 of the half bearing 40, preferably by welding, and is provided with a depending laterally projecting portion 58 provided With a terminal screw 59 for connection of a ground wire thereto, and this ground strap has a tongue extension 60 bent as shown in FIG. 4 to provide a spring latch with a nose portion 61 which is adapted to engage in one of the indentations 31 of the sleeve 30, when the heater is in horizontal position on the spider 21, and impose a spring tension on the indentation to hold the heater in such horizontal position.

Moreover, the extent of tilting permitted by the above mentioned stop lug 56 is such that when the heater is tilted up to the desired upraised position for cleaning, the nose portion 61 of the spring latch is engaged in another one of the indentations 31 so as to releasably hold the heater in such upraised position.

This spring latch 60 extends upwardly at the inner side of the hearing which is nearest to the mounting ring and the inner side Wall 44 of the half bearing 46 is provided with an appropriate opening 62 through which the latch 60 projects for engagement with the sleeve 30 and indentations 31 thereof.

The sleeve 30 as thus formed with its integral flange 32 and indentations 31, not only serves to hold the sheath end in assembled relation, but also provides facilities for restricting endwise and rotational movement of the pivoting shank portion of the heater in the bearing and also provides latching facilities, thereby simplifying the construction.

Moreover, in the use of the heater, strains are imposed on the assembly of the sheath end portions which may tend to cause loosening up and displacement thereof relatively to the sleeve, and the securing of the sheath end portions in place by the indentations assures permanent clamping of the sleeve in fixed position on the sheath end portions, and also facilitates reliable sealing of the interior of the assembly against passage of spillage therethrough.

While I have shown and described my invention in a preferred form, I am aware that various changes and modifications may be made therein without departing from the principles of the invention, the scope of which is to be determined by the appended claims.

What is claimed is:

1. An electric heater assembly comprising a mounting providing an upwardly presented opening and having a bearing disposed beyond the opening at one side thereof, and a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a fiat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening, the heating element having the opposite end portions thereof projecting from the grid and serving as mounting stems therefor which are collectively mounted in the bearing for collective rotation therein providing swinging movement of the grid upwardly from said horizontal position thereof at the top of the opening to an upraised position at one side thereof, the bearing having a sleeve journaled therein which encircles and compactly confines the stems serially therein in adjacent consecutive parallel relation around the axis of rotation of the sleeve in the bearing, and the sleeve having a part of the wall thereof extending between adjacent ones of the stems and into the path of rotation thereof and providing 6 positive relative rotational interlocking of the sleeve on the stems and positive rotation of the sleeve in unison with the stems.

2. An electric heater assembly comprising a mounting providing an upwardly presented opening and having a bearing disposed beyond the opening at one side thereof, and a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a fiat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening, the heating element having the opposite end portions thereof projecting from the grid and serving as mounting stems therefor which are collectively mounted in the bearing for collective rotation therein providing swinging movement of the grid upwardly from said horizontal position thereof at the top of the opening to an upraised position at one side thereof, the bearing having a sleeve journaled therein which encircles and compactly confines the stems serially therein in adjacent consecutive parallel relation around the axis of rotation of the sleeve in the bearing, and the sleeve wall having a portion thereof projecting inwardly between and clamped against adjacent ones of the stems in intervening keying relation thereagainst providing positive relative rotational interlocking of the sleeve on the stems and positive rotation of the sleeve in unison with the stems.

3. An electric heater assembly comprising a heater mounting providing an upwardly presented opening, a plurality of elongated tubular sheathed electrical heating ele ments having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a flat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening, said heating elements having the opposite end portions thereof projecting from the grid and serving as mounting stems therefor, and sleeve means to which said mounting stems are secured and by which the grid is hinged to the mounting at one side of the opening to swing away from the top of the opening, the stems being secured in the sleeve means in adjacent generally parallel relation by a sleeve forming wall of the sleeve means which said wall extends along a portion of the length of each of the stems and has portions thereof offset respectively between each adjacent pair of said stems in circumferential conformity therewith and forming an individual seat for each stem in which the stem is clamped.

4. An electric heater assembly comprising a heater mounting providing an upwardly presented opening, a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a flat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening, said heating elements having the opposite end portions thereof projecting from the grid and serving as mounting stems therefor, and sleeve means to which said mounting stems are secured and by which the grid is hinged to the mounting at one side of the opening to swing away from the top of the opening, the stems being secured in the sleeve means in adjacent generally parallel relation by a sleeve forming wall of the sleeve means which said wall extends along a portion of the length of each of the stems and is formed with a series of crimps which are between the opposite extremities of the portions of the stems along which the wall extends and lock said stem portions in the sleeve means.

5. An electric heater assembly comprising a heater mounting providing an upwardly presented opening, a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a flat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening, said heating elements having the op- 7 posite end portions thereof projecting from the grid and serving as mounting stems therefor, and sleeve means to which said mounting stems are secured and by which the grid is hinged to the mounting at one side of the opening to swing away from the top of the opening, the stems being secured in the sleeve means in adjacent generally parallel relation by a sleeve forming wall of the sleeve means which said wall extends along a portion of the length of each of the stems and has portions thereof bent inwardly between each adjoining pair of stems in circumferential conformity therewith and localized in a zone which is spaced from the opposite extremities of the portions of the stems along which the wall extends, said inwardly bent portions providing keys by which the sleeve is locked on the stems to rotate therewith.

6. An electric heater assembly comprising a heater mounting providing an upwardly presented opening, a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a flat heating grid which is removably supported 'on the mounting in a horizontal position at the top of said opening, said heating elements having the opposite end portions thereof projecting from the grid and serving as mounting stems therefor, and sleeve means to which said mounting stems are secured and by which the grid is hinged to the mounting at one side of the opening to swing away from the top of the opening, the stems being secured in the sleeve means in adjacent generally parallel relation by a sleeve forming wall of the sleeve means which said wall extends along a portion of the length of each of the stems and has portions thereof offset respectively between each adjacent pair of said stems in circumferential conformity therewith and forming an individual seat for each stem in which the stem is clamped, and a sealing gasket interposed between the stems and compressed therebetween and thereagainst by the sleeve means.

7. An electrical heater assembly comprising a heater mounting providing an upwardly presented opening, a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a flat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening, said heating elements having the opposite end portions thereof projecting from the grid and serving as mounting stems therefor, and a sleeve in which said mounting stems are secured and by which the grid is hinged to the mounting at one side of the opening to swing away from the top of the opening, the stems being disposed in the sleeve in adjacent generally parallel relation and disposed in circular series around the longitudinal axis of the sleeve and the sleeve having a generally cylindrical wall which extends around the stems and is indented between each adjacent pair of stems in circumferential conformity therewith forming an individual seat for each stem in which it is clamped.

8. An electrical heater assembly comprising a heater mounting providing an upwardly presented opening, a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a flat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening, said heating elements having the opposite end portions thereof projecting from the grid and serving as mounting stems therefor, and a sleeve in which said mounting stems are secured and by which the grid is hinged to the mounting at one side of the opening to swing away from the top of the opening, the sleeve having a generally cylindrical wall which encircles the stems and is formed with a circumferential series of internal seats each of which has a respective one of said stems clamped therein.

9. An electric heater assembly comprising a heater S mounting providing an upwardly presented opening and having -a bearing at one side of the opening, a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a flat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening and hinged in said bearing to swing away from the top of the opening, said bearing having a sleeve rotatably mounted therein and the said heating elements having the opposite end portions thereof projecting from the grid and secured in said sleeve in adjoining side by side relation, said stems being arranged in circular series in the sleeve and the sleeve having the wall thereof extending around the stems and formed with internal seats therearound in which the stems are respectively clamped.

10. An electric heater as defined in claim 9 in which the sleeve is formed with an outturned portion at one end providing an annular flange and the bearing has stop means thereon which straddles the flange and is cooperable therewith to limit endwise movement of the sleeve in the bearing and the flange has a projection thereon which is cooperable with said stop means of the bearing to limit rotation of the sleeve in the bearing.

11. An electric heater assembly comprising a heater mounting providing an upwardly presented opening and having a bearing at one side of the opening, a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a hat heating grid which is removably supported on the mounting in a horizontal position at the top of said openingand hinged in said bearing to swing away from the top of the opening, said bearing having a sleeve rotatably mounted therein and the said heating elements having the opposite end portions thereof projecting from in which it is clamped.

12. An electric heater assembly comprising a heater mounting providing an upwardly presented opening and having a bearing at one side of the opening, a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a flat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening and hinged in said bearing to swing away from the top of the opening, said bearing having a sleeve rotatably mounted therein and the said heating elements having the opposite end portions thereof projecting from the grid and secured in said sleeve in adjoining side by side relation, said stems being arranged in circular series in the sleeve and the sleeve having the wall thereof extending around the stems and indented between each adjoining pair of stems in circumferential conformity therewith whereby an indivadual seat is formed for each stem in which it is clamped, said wall having an external recess at each place where it is indented and the bearing having a spring latch thereon with a nose portion receivable in at least one of said external recesses and cooperable therewith to releasably hold the heating grid in the position to which it swings away from the opening.

13. An electric heater assembly comprising a heater mounting providing an upwardly presented opening and having a bearing at one side of the opening, a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a flat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening and hinged in said bearing to swing away from the top of the opening, said bearing having a sleeve rotatably mounted therein and the said heating elements having the opposite end portions thereof projecting from the grid and secured in said sleeve in adjoining side by side relation, said stems being arranged in circular series in the sleeve around a sealing gasket and the sleeve having the wall thereof deformed around the stems at the place where the gasket is located and the gasket being compressed by the deformed wall.

14. An electric heater assembly comprising a heater mounting providing an upwardly presented opening and having a bearing at one side of the opening, a plurality of elongated tubular sheathed electrical heating elements having respective uniplanar coiled portions thereof distributively arranged in a common plane and conjointly forming a flat heating grid which is removably supported on the mounting in a horizontal position at the top of said opening and hinged in said bearing to swing away from the top of the opening, said bearing having a sleeve rotatably mounted therein and the said heating elements having the opposite end portions thereof projecting from the grid and secured in said sleeve in adjoining side by side relation, said stems being arranged in circular series in the sleeve around a sealing gasket provided with arm portions projecting therefrom between the adjoining stems and said adjoining stems having matching indentations through which said arms extend and the sleeve having the wall thereof deformed around the stems at the place where the gasket is located and compressed against the stems and against the outer ends of the gasket arms therebetween.

References Cited in the file of this patent UNITED STATES PATENTS 2,824,206 Snyder et a1 Feb. 18, 1958 2,831,100 Kelly Apr. 15, 1958 2,834,863 Anderson et al. May 13, 1958 

14. AN ELECTRIC HEATER ASSEMBLY COMPRISING A HEATER MOUNTING PROVIDING AN UPWARDLY PRESENTED OPENING AND HAVING A BEARING AT ONE SIDE OF THE OPENING, A PLURALITY OF ELONGATED TUBULAR SHEATHED ELECTRICAL HEATING ELEMENTS HAVING RESPECTIVE UNIPLANAR COILED PORTIONS THEREOF DISTRIBUTIVELY ARRANGED IN A COMMON PLANE AND CONJOINTLY FORMING A FLAT HEATING GRID WHICH IS REMOVABLY SUPPORTED ON THE MOUNTING IN A HORIZONTAL POSITION AT THE TOP OF SAID OPENING AND HINGED IN SAID BEARING TO SWING AWAY FROM THE TOP OF THE OPENING, SAID BEARING HAVING A SLEEVE ROTATABLY MOUNTED THEREIN AND THE SAID HEATING ELEMENTS HAVING THE OPPOSITE END PORTIONS THEREOF PROJECTING FROM THE GRID AND SECURED IN SAID SLEEVE IN ADJOINING SIDE BY SIDE RELATION, SAID STEMS BEING ARRANGED IN CIRCULAR SERIES IN THE SLEEVE AROUND A SEALING GASKET PROVIDED WITH ARM PORTIONS PROJECTING THEREFROM BETWEEN THE ADJOINING STEMS AND SAID ADJOINING STEMS HAVING MATCHING INDENTATIONS THROUGH WHICH SAID ARMS EXTEND AND THE SLEEVE HAVING THE WALL THEREOF DEFORMED AROUND THE STEMS AT THE PLACE WHERE THE GASKET IS LOCATED AND COMPRESSED AGAINST THE STEMS AND AGAINST THE OUTER ENDS OF THE GASKET ARMS THEREBETWEEN. 